Saw-grinding machine.



A. ELROD. SAW GRINDING MACHINE APPLICATION FILED MAR.B, 191s.

Patented Sept. 23, 1913.

2 SHEETS-SHBET 1 931 i [Mano on F ZQ.

A. BLROD.

SAW GRINDING MACHINE.

APPLICATION FILED MARB, 191s.

Patented Sept. 23, 1913.

' BHELIJS-SHEE12 @Hoznmp ABRAHAM ELROD, 0F SEYMOUR, INDIANA.

SAW-GRINDING MACHINE.

Specification of Letters Patent.

Application filed March 8, 1913.

atented Sept. 23, .1913

Serial No. 753,004.

To all VGA/H1717: may concern Be it known that .l, Annunnr l binrm, acitizen of the United States, residing at Seymour, Jackson county, andState oil lndiana, have invented and discovered certain new and useful'lmprovemeuts in Saw- (irrinding Machines, oi? which the following is aspecification.

My invention relates to saw grinding uni-- chines and its object is toprovide means to prevent burning of the saw teeth during the grindingoperation, to obtain a uniform grinding pressure on the teeth and toliacilitate the relative travel. oi? the saw and the grinding wheel asthe successive teeth of the saw are brought into contact with the wheel.

With these objects in view, my invention is embodied in preferable formin the device hereinafter described and illustrated in the accompanyingdrawings.

In these drawings, Figure 1, is a detail elevation of apart of agrinding machine showing the grinding wheel in engagement with a sawtooth; Fig. 2, a central vertical section; Fig. 3, a cross section online 3--3 of Fig. Fig. 4 an end view, and Fig. 5, a perspective view.

Referring to the drawings, 1 indicates a shaft or arbor adapted to besuitably mounted in a saw grinding machine of usual con struction andadapted to be rotatably driven. A collar 2 is fixed on the arbor. Fixedon or formed integrally with the arbor 1 are bearing rings 3, spacedapart. Mounted upon these rings is a hub l, having fixed thereto thedisk 5 and being threaded on its outer surface adjacent its outer end toreceive an interiorly threaded disk 6, which is adjustable by means ofthe screw threads. A grinding wheel 7 of emery or other suitablematerial is clamped between the two disks 5 and 6. The hub 4 is heldagainst rotation independently of the arbor 1, by means of alongitudinal key S but said hub is permitted a movement longitudinallyof the arbor on the bearing rings 3. These rings 3 serve to provide abearing surface of small area for the hub whereby the friction due tothe longitudinally sliding movement of the hub is lessened.

Extending radially and also outwardly at an angle from the outer face ofthe disk 5 are separated flat spring arms 9, the free ends of which areadapted to bear against the outer face of the fixed collar 2. EX-tending angularly and radially from the outer face of the disk (3 areseparated lat springs 10. These springs, like the springs t), inarrangement, form a truncated cone. The springs t) and springs 10 aremade oil comparatively light and thin metal and the force of the outersprings 10 is exerted against the grinding wheel with a force sufhcientto sustain yieldingly the weight of the wheel and the disks and theirhub. The arbor is mounted at an inclination between the horizontal andvertical so that the tendency of ti a grinding wheel is to slidedownwardly toward the outer end thereof. If desired, the inner set ofsprings 9 may be dispensed with, the tendency of the wheel to movedownwardly due to gravity being sullicient to maintain the wheelyieldingly in its normal position on the shaft, and to cause it to bearwith su'flicient pressure against the saw teeth.

Adjustably fixed on the arbor 1, near the outer end thereof is a collar11 adapted to be held in position on the arbor by means of set screws 12which bear against the arbor. The springs 10 are adapted to bear againstthe inner face of this collar and by adjusting the collar on the shaftin Or out, the pressure of the springs may be regulated.

In Fig. 1 the grinding wheel is shown in position for grinding a tooth.As the shaft is driven, thus turning the grinding wheel, the latter willbear against the front edge of the tooth. As the saw is advanced thewheel will be lifted up so as to follow the contour of the tooth andbear on the ba k edge thereof.

lVith the ordinary construction of grinding machine the bearing pressureof the wheel against the. tooth is fixed and consequently should therebe a slight inequality in the teeth so tl at one projects toward thewheel. to a greater degree than the others, or should there be anyvariation in the relative positions of the teeth and the wheel due toany irregularity in the saw or in the operation of the saw advancingmechanism then also the wheel will be brought to bear against the teethwith a greater force than is necessary or desirable. The result of toogreat a pressure of the wheel against the teeth is what is termedburning of the tooth, that is such a hardening of the metal as willrender the tooth brittle and liable to be easily broken and incapable ofbeing swaged without danger of breaking the same. If the tooth is notadvanced suificiently far, the wheel, in the ordinary construction, willnot be carried against the tooth with the proper pressure. With myinvention as above described it will be seen that the grinding wheel isadapted to move automatically under a yielding pressure to and from theedge of the teeth in order to yield to obstructions and inequalitieswhile at the same time the wheel is held against the teeth withsufiicient force to insure a uniform pressure thereon. In my invent-ionthe emery Wheel and its supporting disks and hub are alone movablelongitudinally and the arbor remains stationary relative to suchlongitudinal movement, whereby the objections due to the resistanceoffered to the movement of the wheel by the weight of the arbor and thetension of the belt on the pulley are obviated.

The separate fiat springs projecting radially and angularly from theface of the emery wheel clamping disk have been found to provideyielding pressure means very satisfactory in operation and to avoid binding or friction of such means and yet to impart suflicient pressure tothe disk to insure its return without the necessity of employing springsof great strength. This result is due to the fact that the springs haveno bearing against the arbor, that they are disposed circularly atequally distant points around the disk and that their outer ends aresecured to the disk at the perimeter of the latter.

Having thus described my invention what I claim is: p p

1 In a saw grinding machine, in combination with a grinding wheel, arotating arbor,a hub carrying said'wheel andmounted'on'said arbor andmovable longitudinally on the arbor underthe pressure of the saw tooth,substantially as described. 7

2. In a saw grinding machine, incombination with a grinding wheel, arotatable downwardly inclined arbor, means to drive said arbor, a hubcarried at the lower end of the arbor, andin which said wheel is fixed,said hub being mounted to have free movement longitudinally of saidarbor, and spring means bearing against the hub on the lower sidethereof, substantially as described.

3. In a saw grinding machine, in combi Copies of this oatent may beobtained for five cents each by addressing" the Commissioner of Patents,

nation with a rotatable arbor, a grinding wheel mounted to rotate withsaid arbor and automatically movable longitudinally thereon and operableto exert a yielding pressure against the saw tooth, substantially asdescribed.

4;. In a saw grinding machine in combination with a rotatable arbor, agrinding wheel mounted to rotate with said arborand having alongitudinal movement thereon, and spring means on each side of saidwheel to impart a yielding pressure thereto, substantially as described.

5. In a saw grinding machine in combination with a rotatable arbor, agrinding wheel mounted to rotate with but movable longitudinally on saidarbor, a series of separated flat springs projecting radially andangularly from one face of said wheel and means fixed on the arboragainst which said springs bear, substantially as described.

6. In a saw grinding machine, in combination with a rotatable arbor, agrinding wheel, disks between which said wheel is clamped, a hub onwhich said disks are mounted, means to fiX said hub on said arboragainst rotation whileperinitting automatic longitudinal movementthereof, a series of flat springs each secured at one end to the outerface of one of said disks near the perimeter thereof, and extendingradially and angularly from the face of said disk and means fixed on thearbor against which the ends of the springs bear, substan tially asdescribed.

7 In a saw grinding machine, in combination with a rotatable arbor, agrinding wheel mounted for rotation with but having longitudinalmovement independent of said arbor, and spring means exerting pressureagainst said wheel on opposite sides thereof, whereby the wheel is heldagainst the saw tooth with a yielding pressure, substantially asdescribed.

In witness whereof, I have hereunto set my hand and seal atIndianapolis, Indiana, this fifteenth day of February, A. Dpnineteenhundred and thirteen.

ABRAHAM nLnon;

WVitnesses A. C. Bron, H. P. DOOLITTLE.

Washington, D. G.

